The present invention relates to a motor-driven shutter mechanism for use in an optical image producing apparatus, such as a photographic camera or a copying machine, of a type which necessitates a shutter mechanism for selectively opening and closing an exposure aperture provided in the apparatus for the passage of the incoming light therethrough.
A shutter mechanism utilizing an electromagnetic control system, that is, a so-called electromagnetically operated shutter mechanism, is well known in the art. This conventional electromagnetically operated shutter mechanism merely gives a maximum shutter speed of not more than 1/30 second due to the fact that less technical consideration has been paid to the design of electromagnetic coils, the type of electromagnets and/or the way they are used. Moreover, since the electromagnetic coils employed in the conventional shutter mechanism are bulky, the overall design of the shutter mechanism is accordingly bulky. When it comes to a photographic camera in which the shutter mechanism is to be employed, there have been some problems to be solved.
Furthermore, although the conventional shutter mechanism utilizing the electromagnetic control system is simple in construction and durable in performance, it has not yet been put into practice, because of the bulky size and unavailability of the high maximum shutter speed.